diff options
Diffstat (limited to 'src/crush/builder.c')
-rw-r--r-- | src/crush/builder.c | 1525 |
1 files changed, 1525 insertions, 0 deletions
diff --git a/src/crush/builder.c b/src/crush/builder.c new file mode 100644 index 00000000..68dfcb69 --- /dev/null +++ b/src/crush/builder.c @@ -0,0 +1,1525 @@ +#include <string.h> +#include <math.h> +#include <stdlib.h> +#include <stdio.h> +#include <assert.h> +#include <errno.h> + +#include "crush/crush.h" +#include "builder.h" + +#define dprintk(args...) /* printf(args) */ + +#define BUG_ON(x) assert(!(x)) + +struct crush_map *crush_create() +{ + struct crush_map *m; + m = malloc(sizeof(*m)); + if (!m) + return NULL; + memset(m, 0, sizeof(*m)); + + set_optimal_crush_map(m); + return m; +} + +/* + * finalize should be called _after_ all buckets are added to the map. + */ +void crush_finalize(struct crush_map *map) +{ + int b; + __u32 i; + + /* Calculate the needed working space while we do other + finalization tasks. */ + map->working_size = sizeof(struct crush_work); + /* Space for the array of pointers to per-bucket workspace */ + map->working_size += map->max_buckets * + sizeof(struct crush_work_bucket *); + + /* calc max_devices */ + map->max_devices = 0; + for (b=0; b<map->max_buckets; b++) { + if (map->buckets[b] == 0) + continue; + for (i=0; i<map->buckets[b]->size; i++) + if (map->buckets[b]->items[i] >= map->max_devices) + map->max_devices = map->buckets[b]->items[i] + 1; + + switch (map->buckets[b]->alg) { + default: + /* The base case, permutation variables and + the pointer to the permutation array. */ + map->working_size += sizeof(struct crush_work_bucket); + break; + } + /* Every bucket has a permutation array. */ + map->working_size += map->buckets[b]->size * sizeof(__u32); + } +} + + + +/** rules **/ + +int crush_add_rule(struct crush_map *map, struct crush_rule *rule, int ruleno) +{ + __u32 r; + + if (ruleno < 0) { + for (r=0; r < map->max_rules; r++) + if (map->rules[r] == 0) + break; + assert(r < CRUSH_MAX_RULES); + } + else + r = ruleno; + + if (r >= map->max_rules) { + /* expand array */ + int oldsize; + void *_realloc = NULL; + if (map->max_rules +1 > CRUSH_MAX_RULES) + return -ENOSPC; + oldsize = map->max_rules; + map->max_rules = r+1; + if ((_realloc = realloc(map->rules, map->max_rules * sizeof(map->rules[0]))) == NULL) { + return -ENOMEM; + } else { + map->rules = _realloc; + } + memset(map->rules + oldsize, 0, (map->max_rules-oldsize) * sizeof(map->rules[0])); + } + + /* add it */ + map->rules[r] = rule; + return r; +} + +struct crush_rule *crush_make_rule(int len, int ruleset, int type, int minsize, int maxsize) +{ + struct crush_rule *rule; + rule = malloc(crush_rule_size(len)); + if (!rule) + return NULL; + rule->len = len; + rule->mask.ruleset = ruleset; + rule->mask.type = type; + rule->mask.min_size = minsize; + rule->mask.max_size = maxsize; + return rule; +} + +/* + * be careful; this doesn't verify that the buffer you allocated is big enough! + */ +void crush_rule_set_step(struct crush_rule *rule, int n, int op, int arg1, int arg2) +{ + assert((__u32)n < rule->len); + rule->steps[n].op = op; + rule->steps[n].arg1 = arg1; + rule->steps[n].arg2 = arg2; +} + + +/** buckets **/ +int crush_get_next_bucket_id(struct crush_map *map) +{ + int pos; + for (pos=0; pos < map->max_buckets; pos++) + if (map->buckets[pos] == 0) + break; + return -1 - pos; +} + + +int crush_add_bucket(struct crush_map *map, + int id, + struct crush_bucket *bucket, + int *idout) +{ + int pos; + + /* find a bucket id */ + if (id == 0) + id = crush_get_next_bucket_id(map); + pos = -1 - id; + + while (pos >= map->max_buckets) { + /* expand array */ + int oldsize = map->max_buckets; + if (map->max_buckets) + map->max_buckets *= 2; + else + map->max_buckets = 8; + void *_realloc = NULL; + if ((_realloc = realloc(map->buckets, map->max_buckets * sizeof(map->buckets[0]))) == NULL) { + return -ENOMEM; + } else { + map->buckets = _realloc; + } + memset(map->buckets + oldsize, 0, (map->max_buckets-oldsize) * sizeof(map->buckets[0])); + } + + if (map->buckets[pos] != 0) { + return -EEXIST; + } + + /* add it */ + bucket->id = id; + map->buckets[pos] = bucket; + + if (idout) *idout = id; + return 0; +} + +int crush_remove_bucket(struct crush_map *map, struct crush_bucket *bucket) +{ + int pos = -1 - bucket->id; + assert(pos < map->max_buckets); + map->buckets[pos] = NULL; + crush_destroy_bucket(bucket); + return 0; +} + + +/* uniform bucket */ + +struct crush_bucket_uniform * +crush_make_uniform_bucket(int hash, int type, int size, + int *items, + int item_weight) +{ + int i; + struct crush_bucket_uniform *bucket; + + bucket = malloc(sizeof(*bucket)); + if (!bucket) + return NULL; + memset(bucket, 0, sizeof(*bucket)); + bucket->h.alg = CRUSH_BUCKET_UNIFORM; + bucket->h.hash = hash; + bucket->h.type = type; + bucket->h.size = size; + + if (crush_multiplication_is_unsafe(size, item_weight)) + goto err; + + bucket->h.weight = size * item_weight; + bucket->item_weight = item_weight; + bucket->h.items = malloc(sizeof(__s32)*size); + + if (!bucket->h.items) + goto err; + + for (i=0; i<size; i++) + bucket->h.items[i] = items[i]; + + return bucket; +err: + free(bucket->h.items); + free(bucket); + return NULL; +} + + +/* list bucket */ + +struct crush_bucket_list* +crush_make_list_bucket(int hash, int type, int size, + int *items, + int *weights) +{ + int i; + int w; + struct crush_bucket_list *bucket; + + bucket = malloc(sizeof(*bucket)); + if (!bucket) + return NULL; + memset(bucket, 0, sizeof(*bucket)); + bucket->h.alg = CRUSH_BUCKET_LIST; + bucket->h.hash = hash; + bucket->h.type = type; + bucket->h.size = size; + + bucket->h.items = malloc(sizeof(__s32)*size); + if (!bucket->h.items) + goto err; + + + bucket->item_weights = malloc(sizeof(__u32)*size); + if (!bucket->item_weights) + goto err; + bucket->sum_weights = malloc(sizeof(__u32)*size); + if (!bucket->sum_weights) + goto err; + w = 0; + for (i=0; i<size; i++) { + bucket->h.items[i] = items[i]; + bucket->item_weights[i] = weights[i]; + + if (crush_addition_is_unsafe(w, weights[i])) + goto err; + + w += weights[i]; + bucket->sum_weights[i] = w; + /*dprintk("pos %d item %d weight %d sum %d\n", + i, items[i], weights[i], bucket->sum_weights[i]);*/ + } + + bucket->h.weight = w; + + return bucket; +err: + free(bucket->sum_weights); + free(bucket->item_weights); + free(bucket->h.items); + free(bucket); + return NULL; +} + + +/* tree bucket */ + +static int height(int n) { + int h = 0; + while ((n & 1) == 0) { + h++; + n = n >> 1; + } + return h; +} +static int on_right(int n, int h) { + return n & (1 << (h+1)); +} +static int parent(int n) +{ + int h = height(n); + if (on_right(n, h)) + return n - (1<<h); + else + return n + (1<<h); +} + +static int calc_depth(int size) +{ + if (size == 0) { + return 0; + } + + int depth = 1; + int t = size - 1; + while (t) { + t = t >> 1; + depth++; + } + return depth; +} + +struct crush_bucket_tree* +crush_make_tree_bucket(int hash, int type, int size, + int *items, /* in leaf order */ + int *weights) +{ + struct crush_bucket_tree *bucket; + int depth; + int node; + int i, j; + + bucket = malloc(sizeof(*bucket)); + if (!bucket) + return NULL; + memset(bucket, 0, sizeof(*bucket)); + bucket->h.alg = CRUSH_BUCKET_TREE; + bucket->h.hash = hash; + bucket->h.type = type; + bucket->h.size = size; + + if (size == 0) { + bucket->h.items = NULL; + bucket->h.weight = 0; + bucket->node_weights = NULL; + bucket->num_nodes = 0; + /* printf("size 0 depth 0 nodes 0\n"); */ + return bucket; + } + + bucket->h.items = malloc(sizeof(__s32)*size); + if (!bucket->h.items) + goto err; + + /* calc tree depth */ + depth = calc_depth(size); + bucket->num_nodes = 1 << depth; + dprintk("size %d depth %d nodes %d\n", size, depth, bucket->num_nodes); + + bucket->node_weights = malloc(sizeof(__u32)*bucket->num_nodes); + if (!bucket->node_weights) + goto err; + + memset(bucket->h.items, 0, sizeof(__s32)*bucket->h.size); + memset(bucket->node_weights, 0, sizeof(__u32)*bucket->num_nodes); + + for (i=0; i<size; i++) { + bucket->h.items[i] = items[i]; + node = crush_calc_tree_node(i); + dprintk("item %d node %d weight %d\n", i, node, weights[i]); + bucket->node_weights[node] = weights[i]; + + if (crush_addition_is_unsafe(bucket->h.weight, weights[i])) + goto err; + + bucket->h.weight += weights[i]; + for (j=1; j<depth; j++) { + node = parent(node); + + if (crush_addition_is_unsafe(bucket->node_weights[node], weights[i])) + goto err; + + bucket->node_weights[node] += weights[i]; + dprintk(" node %d weight %d\n", node, bucket->node_weights[node]); + } + } + BUG_ON(bucket->node_weights[bucket->num_nodes/2] != bucket->h.weight); + + return bucket; +err: + free(bucket->node_weights); + free(bucket->h.items); + free(bucket); + return NULL; +} + + + +/* straw bucket */ + +/* + * this code was written 8 years ago. i have a vague recollection of + * drawing boxes underneath bars of different lengths, where the bar + * length represented the probability/weight, and that there was some + * trial and error involved in arriving at this implementation. + * however, reading the code now after all this time, the intuition + * that motivated is lost on me. lame. my only excuse is that I now + * know that the approach is fundamentally flawed and am not + * particularly motivated to reconstruct the flawed reasoning. + * + * as best as i can remember, the idea is: sort the weights, and start + * with the smallest. arbitrarily scale it at 1.0 (16-bit fixed + * point). look at the next larger weight, and calculate the scaling + * factor for that straw based on the relative difference in weight so + * far. what's not clear to me now is why we are looking at wnext + * (the delta to the next bigger weight) for all remaining weights, + * and slicing things horizontally instead of considering just the + * next item or set of items. or why pow() is used the way it is. + * + * note that the original version 1 of this function made special + * accommodation for the case where straw lengths were identical. this + * is also flawed in a non-obvious way; version 2 drops the special + * handling and appears to work just as well. + * + * moral of the story: if you do something clever, write down why it + * works. + */ +int crush_calc_straw(struct crush_map *map, struct crush_bucket_straw *bucket) +{ + int *reverse; + int i, j, k; + double straw, wbelow, lastw, wnext, pbelow; + int numleft; + int size = bucket->h.size; + __u32 *weights = bucket->item_weights; + + /* reverse sort by weight (simple insertion sort) */ + reverse = malloc(sizeof(int) * size); + if (!reverse) + return -ENOMEM; + if (size) + reverse[0] = 0; + for (i=1; i<size; i++) { + for (j=0; j<i; j++) { + if (weights[i] < weights[reverse[j]]) { + /* insert here */ + for (k=i; k>j; k--) + reverse[k] = reverse[k-1]; + reverse[j] = i; + break; + } + } + if (j == i) + reverse[i] = i; + } + + numleft = size; + straw = 1.0; + wbelow = 0; + lastw = 0; + + i=0; + while (i < size) { + if (map->straw_calc_version == 0) { + /* zero weight items get 0 length straws! */ + if (weights[reverse[i]] == 0) { + bucket->straws[reverse[i]] = 0; + i++; + continue; + } + + /* set this item's straw */ + bucket->straws[reverse[i]] = straw * 0x10000; + dprintk("item %d at %d weight %d straw %d (%lf)\n", + bucket->h.items[reverse[i]], + reverse[i], weights[reverse[i]], + bucket->straws[reverse[i]], straw); + i++; + if (i == size) + break; + + /* same weight as previous? */ + if (weights[reverse[i]] == weights[reverse[i-1]]) { + dprintk("same as previous\n"); + continue; + } + + /* adjust straw for next guy */ + wbelow += ((double)weights[reverse[i-1]] - lastw) * + numleft; + for (j=i; j<size; j++) + if (weights[reverse[j]] == weights[reverse[i]]) + numleft--; + else + break; + wnext = numleft * (weights[reverse[i]] - + weights[reverse[i-1]]); + pbelow = wbelow / (wbelow + wnext); + dprintk("wbelow %lf wnext %lf pbelow %lf numleft %d\n", + wbelow, wnext, pbelow, numleft); + + straw *= pow((double)1.0 / pbelow, (double)1.0 / + (double)numleft); + + lastw = weights[reverse[i-1]]; + } else if (map->straw_calc_version >= 1) { + /* zero weight items get 0 length straws! */ + if (weights[reverse[i]] == 0) { + bucket->straws[reverse[i]] = 0; + i++; + numleft--; + continue; + } + + /* set this item's straw */ + bucket->straws[reverse[i]] = straw * 0x10000; + dprintk("item %d at %d weight %d straw %d (%lf)\n", + bucket->h.items[reverse[i]], + reverse[i], weights[reverse[i]], + bucket->straws[reverse[i]], straw); + i++; + if (i == size) + break; + + /* adjust straw for next guy */ + wbelow += ((double)weights[reverse[i-1]] - lastw) * + numleft; + numleft--; + wnext = numleft * (weights[reverse[i]] - + weights[reverse[i-1]]); + pbelow = wbelow / (wbelow + wnext); + dprintk("wbelow %lf wnext %lf pbelow %lf numleft %d\n", + wbelow, wnext, pbelow, numleft); + + straw *= pow((double)1.0 / pbelow, (double)1.0 / + (double)numleft); + + lastw = weights[reverse[i-1]]; + } + } + + free(reverse); + return 0; +} + +struct crush_bucket_straw * +crush_make_straw_bucket(struct crush_map *map, + int hash, + int type, + int size, + int *items, + int *weights) +{ + struct crush_bucket_straw *bucket; + int i; + + bucket = malloc(sizeof(*bucket)); + if (!bucket) + return NULL; + memset(bucket, 0, sizeof(*bucket)); + bucket->h.alg = CRUSH_BUCKET_STRAW; + bucket->h.hash = hash; + bucket->h.type = type; + bucket->h.size = size; + + bucket->h.items = malloc(sizeof(__s32)*size); + if (!bucket->h.items) + goto err; + bucket->item_weights = malloc(sizeof(__u32)*size); + if (!bucket->item_weights) + goto err; + bucket->straws = malloc(sizeof(__u32)*size); + if (!bucket->straws) + goto err; + + bucket->h.weight = 0; + for (i=0; i<size; i++) { + bucket->h.items[i] = items[i]; + bucket->h.weight += weights[i]; + bucket->item_weights[i] = weights[i]; + } + + if (crush_calc_straw(map, bucket) < 0) + goto err; + + return bucket; +err: + free(bucket->straws); + free(bucket->item_weights); + free(bucket->h.items); + free(bucket); + return NULL; +} + +struct crush_bucket_straw2 * +crush_make_straw2_bucket(struct crush_map *map, + int hash, + int type, + int size, + int *items, + int *weights) +{ + struct crush_bucket_straw2 *bucket; + int i; + + bucket = malloc(sizeof(*bucket)); + if (!bucket) + return NULL; + memset(bucket, 0, sizeof(*bucket)); + bucket->h.alg = CRUSH_BUCKET_STRAW2; + bucket->h.hash = hash; + bucket->h.type = type; + bucket->h.size = size; + + bucket->h.items = malloc(sizeof(__s32)*size); + if (!bucket->h.items) + goto err; + bucket->item_weights = malloc(sizeof(__u32)*size); + if (!bucket->item_weights) + goto err; + + bucket->h.weight = 0; + for (i=0; i<size; i++) { + bucket->h.items[i] = items[i]; + bucket->h.weight += weights[i]; + bucket->item_weights[i] = weights[i]; + } + + return bucket; +err: + free(bucket->item_weights); + free(bucket->h.items); + free(bucket); + return NULL; +} + + + +struct crush_bucket* +crush_make_bucket(struct crush_map *map, + int alg, int hash, int type, int size, + int *items, + int *weights) +{ + int item_weight; + + switch (alg) { + case CRUSH_BUCKET_UNIFORM: + if (size && weights) + item_weight = weights[0]; + else + item_weight = 0; + return (struct crush_bucket *)crush_make_uniform_bucket(hash, type, size, items, item_weight); + + case CRUSH_BUCKET_LIST: + return (struct crush_bucket *)crush_make_list_bucket(hash, type, size, items, weights); + + case CRUSH_BUCKET_TREE: + return (struct crush_bucket *)crush_make_tree_bucket(hash, type, size, items, weights); + + case CRUSH_BUCKET_STRAW: + return (struct crush_bucket *)crush_make_straw_bucket(map, hash, type, size, items, weights); + case CRUSH_BUCKET_STRAW2: + return (struct crush_bucket *)crush_make_straw2_bucket(map, hash, type, size, items, weights); + } + return 0; +} + + +/************************************************/ + +int crush_add_uniform_bucket_item(struct crush_bucket_uniform *bucket, int item, int weight) +{ + int newsize = bucket->h.size + 1; + void *_realloc = NULL; + + /* In such situation 'CRUSH_BUCKET_UNIFORM', the weight + provided for the item should be the same as + bucket->item_weight defined with 'crush_make_bucket'. This + assumption is enforced by the return value which is always + 0. */ + if (bucket->item_weight != weight) { + return -EINVAL; + } + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + + bucket->h.items[newsize-1] = item; + + if (crush_addition_is_unsafe(bucket->h.weight, weight)) + return -ERANGE; + + bucket->h.weight += weight; + bucket->h.size++; + + return 0; +} + +int crush_add_list_bucket_item(struct crush_bucket_list *bucket, int item, int weight) +{ + int newsize = bucket->h.size + 1; + void *_realloc = NULL; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + if ((_realloc = realloc(bucket->item_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->item_weights = _realloc; + } + if ((_realloc = realloc(bucket->sum_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->sum_weights = _realloc; + } + + bucket->h.items[newsize-1] = item; + bucket->item_weights[newsize-1] = weight; + if (newsize > 1) { + + if (crush_addition_is_unsafe(bucket->sum_weights[newsize-2], weight)) + return -ERANGE; + + bucket->sum_weights[newsize-1] = bucket->sum_weights[newsize-2] + weight; + } + + else { + bucket->sum_weights[newsize-1] = weight; + } + + bucket->h.weight += weight; + bucket->h.size++; + return 0; +} + +int crush_add_tree_bucket_item(struct crush_bucket_tree *bucket, int item, int weight) +{ + int newsize = bucket->h.size + 1; + int depth = calc_depth(newsize);; + int node; + int j; + void *_realloc = NULL; + + bucket->num_nodes = 1 << depth; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + if ((_realloc = realloc(bucket->node_weights, sizeof(__u32)*bucket->num_nodes)) == NULL) { + return -ENOMEM; + } else { + bucket->node_weights = _realloc; + } + + node = crush_calc_tree_node(newsize-1); + bucket->node_weights[node] = weight; + + /* if the depth increase, we need to initialize the new root node's weight before add bucket item */ + int root = bucket->num_nodes/2; + if (depth >= 2 && (node - 1) == root) { + /* if the new item is the first node in right sub tree, so + * the root node initial weight is left sub tree's weight + */ + bucket->node_weights[root] = bucket->node_weights[root/2]; + } + + for (j=1; j<depth; j++) { + node = parent(node); + + if (crush_addition_is_unsafe(bucket->node_weights[node], weight)) + return -ERANGE; + + bucket->node_weights[node] += weight; + dprintk(" node %d weight %d\n", node, bucket->node_weights[node]); + } + + + if (crush_addition_is_unsafe(bucket->h.weight, weight)) + return -ERANGE; + + bucket->h.items[newsize-1] = item; + bucket->h.weight += weight; + bucket->h.size++; + + return 0; +} + +int crush_add_straw_bucket_item(struct crush_map *map, + struct crush_bucket_straw *bucket, + int item, int weight) +{ + int newsize = bucket->h.size + 1; + + void *_realloc = NULL; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + if ((_realloc = realloc(bucket->item_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->item_weights = _realloc; + } + if ((_realloc = realloc(bucket->straws, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->straws = _realloc; + } + + bucket->h.items[newsize-1] = item; + bucket->item_weights[newsize-1] = weight; + + if (crush_addition_is_unsafe(bucket->h.weight, weight)) + return -ERANGE; + + bucket->h.weight += weight; + bucket->h.size++; + + return crush_calc_straw(map, bucket); +} + +int crush_add_straw2_bucket_item(struct crush_map *map, + struct crush_bucket_straw2 *bucket, + int item, int weight) +{ + int newsize = bucket->h.size + 1; + + void *_realloc = NULL; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + if ((_realloc = realloc(bucket->item_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->item_weights = _realloc; + } + + bucket->h.items[newsize-1] = item; + bucket->item_weights[newsize-1] = weight; + + if (crush_addition_is_unsafe(bucket->h.weight, weight)) + return -ERANGE; + + bucket->h.weight += weight; + bucket->h.size++; + + return 0; +} + +int crush_bucket_add_item(struct crush_map *map, + struct crush_bucket *b, int item, int weight) +{ + switch (b->alg) { + case CRUSH_BUCKET_UNIFORM: + return crush_add_uniform_bucket_item((struct crush_bucket_uniform *)b, item, weight); + case CRUSH_BUCKET_LIST: + return crush_add_list_bucket_item((struct crush_bucket_list *)b, item, weight); + case CRUSH_BUCKET_TREE: + return crush_add_tree_bucket_item((struct crush_bucket_tree *)b, item, weight); + case CRUSH_BUCKET_STRAW: + return crush_add_straw_bucket_item(map, (struct crush_bucket_straw *)b, item, weight); + case CRUSH_BUCKET_STRAW2: + return crush_add_straw2_bucket_item(map, (struct crush_bucket_straw2 *)b, item, weight); + default: + return -1; + } +} + +/************************************************/ + +int crush_remove_uniform_bucket_item(struct crush_bucket_uniform *bucket, int item) +{ + unsigned i, j; + int newsize; + void *_realloc = NULL; + + for (i = 0; i < bucket->h.size; i++) + if (bucket->h.items[i] == item) + break; + if (i == bucket->h.size) + return -ENOENT; + + for (j = i; j < bucket->h.size; j++) + bucket->h.items[j] = bucket->h.items[j+1]; + newsize = --bucket->h.size; + if (bucket->item_weight < bucket->h.weight) + bucket->h.weight -= bucket->item_weight; + else + bucket->h.weight = 0; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + return 0; +} + +int crush_remove_list_bucket_item(struct crush_bucket_list *bucket, int item) +{ + unsigned i, j; + int newsize; + unsigned weight; + + for (i = 0; i < bucket->h.size; i++) + if (bucket->h.items[i] == item) + break; + if (i == bucket->h.size) + return -ENOENT; + + weight = bucket->item_weights[i]; + for (j = i; j < bucket->h.size; j++) { + bucket->h.items[j] = bucket->h.items[j+1]; + bucket->item_weights[j] = bucket->item_weights[j+1]; + bucket->sum_weights[j] = bucket->sum_weights[j+1] - weight; + } + if (weight < bucket->h.weight) + bucket->h.weight -= weight; + else + bucket->h.weight = 0; + newsize = --bucket->h.size; + + void *_realloc = NULL; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + if ((_realloc = realloc(bucket->item_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->item_weights = _realloc; + } + if ((_realloc = realloc(bucket->sum_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->sum_weights = _realloc; + } + return 0; +} + +int crush_remove_tree_bucket_item(struct crush_bucket_tree *bucket, int item) +{ + unsigned i; + unsigned newsize; + + for (i = 0; i < bucket->h.size; i++) { + int node; + unsigned weight; + int j; + int depth = calc_depth(bucket->h.size); + + if (bucket->h.items[i] != item) + continue; + + bucket->h.items[i] = 0; + node = crush_calc_tree_node(i); + weight = bucket->node_weights[node]; + bucket->node_weights[node] = 0; + + for (j = 1; j < depth; j++) { + node = parent(node); + bucket->node_weights[node] -= weight; + dprintk(" node %d weight %d\n", node, bucket->node_weights[node]); + } + if (weight < bucket->h.weight) + bucket->h.weight -= weight; + else + bucket->h.weight = 0; + break; + } + if (i == bucket->h.size) + return -ENOENT; + + newsize = bucket->h.size; + while (newsize > 0) { + int node = crush_calc_tree_node(newsize - 1); + if (bucket->node_weights[node]) + break; + --newsize; + } + + if (newsize != bucket->h.size) { + int olddepth, newdepth; + + void *_realloc = NULL; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + + olddepth = calc_depth(bucket->h.size); + newdepth = calc_depth(newsize); + if (olddepth != newdepth) { + bucket->num_nodes = 1 << newdepth; + if ((_realloc = realloc(bucket->node_weights, + sizeof(__u32)*bucket->num_nodes)) == NULL) { + return -ENOMEM; + } else { + bucket->node_weights = _realloc; + } + } + + bucket->h.size = newsize; + } + return 0; +} + +int crush_remove_straw_bucket_item(struct crush_map *map, + struct crush_bucket_straw *bucket, int item) +{ + int newsize = bucket->h.size - 1; + unsigned i, j; + + for (i = 0; i < bucket->h.size; i++) { + if (bucket->h.items[i] == item) { + if (bucket->item_weights[i] < bucket->h.weight) + bucket->h.weight -= bucket->item_weights[i]; + else + bucket->h.weight = 0; + for (j = i; j < bucket->h.size - 1; j++) { + bucket->h.items[j] = bucket->h.items[j+1]; + bucket->item_weights[j] = bucket->item_weights[j+1]; + } + break; + } + } + if (i == bucket->h.size) + return -ENOENT; + bucket->h.size--; + if (bucket->h.size == 0) { + /* don't bother reallocating */ + return 0; + } + void *_realloc = NULL; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + if ((_realloc = realloc(bucket->item_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->item_weights = _realloc; + } + if ((_realloc = realloc(bucket->straws, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->straws = _realloc; + } + + return crush_calc_straw(map, bucket); +} + +int crush_remove_straw2_bucket_item(struct crush_map *map, + struct crush_bucket_straw2 *bucket, int item) +{ + int newsize = bucket->h.size - 1; + unsigned i, j; + + for (i = 0; i < bucket->h.size; i++) { + if (bucket->h.items[i] == item) { + if (bucket->item_weights[i] < bucket->h.weight) + bucket->h.weight -= bucket->item_weights[i]; + else + bucket->h.weight = 0; + for (j = i; j < bucket->h.size - 1; j++) { + bucket->h.items[j] = bucket->h.items[j+1]; + bucket->item_weights[j] = bucket->item_weights[j+1]; + } + break; + } + } + if (i == bucket->h.size) + return -ENOENT; + + bucket->h.size--; + if (!newsize) { + /* don't bother reallocating a 0-length array. */ + return 0; + } + + void *_realloc = NULL; + + if ((_realloc = realloc(bucket->h.items, sizeof(__s32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->h.items = _realloc; + } + if ((_realloc = realloc(bucket->item_weights, sizeof(__u32)*newsize)) == NULL) { + return -ENOMEM; + } else { + bucket->item_weights = _realloc; + } + + return 0; +} + +int crush_bucket_remove_item(struct crush_map *map, struct crush_bucket *b, int item) +{ + switch (b->alg) { + case CRUSH_BUCKET_UNIFORM: + return crush_remove_uniform_bucket_item((struct crush_bucket_uniform *)b, item); + case CRUSH_BUCKET_LIST: + return crush_remove_list_bucket_item((struct crush_bucket_list *)b, item); + case CRUSH_BUCKET_TREE: + return crush_remove_tree_bucket_item((struct crush_bucket_tree *)b, item); + case CRUSH_BUCKET_STRAW: + return crush_remove_straw_bucket_item(map, (struct crush_bucket_straw *)b, item); + case CRUSH_BUCKET_STRAW2: + return crush_remove_straw2_bucket_item(map, (struct crush_bucket_straw2 *)b, item); + default: + return -1; + } +} + + +/************************************************/ + +int crush_adjust_uniform_bucket_item_weight(struct crush_bucket_uniform *bucket, int item, int weight) +{ + int diff = (weight - bucket->item_weight) * bucket->h.size; + + bucket->item_weight = weight; + bucket->h.weight = bucket->item_weight * bucket->h.size; + + return diff; +} + +int crush_adjust_list_bucket_item_weight(struct crush_bucket_list *bucket, int item, int weight) +{ + int diff; + unsigned i, j; + + for (i = 0; i < bucket->h.size; i++) { + if (bucket->h.items[i] == item) + break; + } + if (i == bucket->h.size) + return 0; + + diff = weight - bucket->item_weights[i]; + bucket->item_weights[i] = weight; + bucket->h.weight += diff; + + for (j = i; j < bucket->h.size; j++) + bucket->sum_weights[j] += diff; + + return diff; +} + +int crush_adjust_tree_bucket_item_weight(struct crush_bucket_tree *bucket, int item, int weight) +{ + int diff; + int node; + unsigned i, j; + unsigned depth = calc_depth(bucket->h.size); + + for (i = 0; i < bucket->h.size; i++) { + if (bucket->h.items[i] == item) + break; + } + if (i == bucket->h.size) + return 0; + + node = crush_calc_tree_node(i); + diff = weight - bucket->node_weights[node]; + bucket->node_weights[node] = weight; + bucket->h.weight += diff; + + for (j=1; j<depth; j++) { + node = parent(node); + bucket->node_weights[node] += diff; + } + + return diff; +} + +int crush_adjust_straw_bucket_item_weight(struct crush_map *map, + struct crush_bucket_straw *bucket, + int item, int weight) +{ + unsigned idx; + int diff; + int r; + + for (idx = 0; idx < bucket->h.size; idx++) + if (bucket->h.items[idx] == item) + break; + if (idx == bucket->h.size) + return 0; + + diff = weight - bucket->item_weights[idx]; + bucket->item_weights[idx] = weight; + bucket->h.weight += diff; + + r = crush_calc_straw(map, bucket); + if (r < 0) + return r; + + return diff; +} + +int crush_adjust_straw2_bucket_item_weight(struct crush_map *map, + struct crush_bucket_straw2 *bucket, + int item, int weight) +{ + unsigned idx; + int diff; + + for (idx = 0; idx < bucket->h.size; idx++) + if (bucket->h.items[idx] == item) + break; + if (idx == bucket->h.size) + return 0; + + diff = weight - bucket->item_weights[idx]; + bucket->item_weights[idx] = weight; + bucket->h.weight += diff; + + return diff; +} + +int crush_bucket_adjust_item_weight(struct crush_map *map, + struct crush_bucket *b, + int item, int weight) +{ + switch (b->alg) { + case CRUSH_BUCKET_UNIFORM: + return crush_adjust_uniform_bucket_item_weight((struct crush_bucket_uniform *)b, + item, weight); + case CRUSH_BUCKET_LIST: + return crush_adjust_list_bucket_item_weight((struct crush_bucket_list *)b, + item, weight); + case CRUSH_BUCKET_TREE: + return crush_adjust_tree_bucket_item_weight((struct crush_bucket_tree *)b, + item, weight); + case CRUSH_BUCKET_STRAW: + return crush_adjust_straw_bucket_item_weight(map, + (struct crush_bucket_straw *)b, + item, weight); + case CRUSH_BUCKET_STRAW2: + return crush_adjust_straw2_bucket_item_weight(map, + (struct crush_bucket_straw2 *)b, + item, weight); + default: + return -1; + } +} + +/************************************************/ + +static int crush_reweight_uniform_bucket(struct crush_map *map, struct crush_bucket_uniform *bucket) +{ + unsigned i; + unsigned sum = 0, n = 0, leaves = 0; + + for (i = 0; i < bucket->h.size; i++) { + int id = bucket->h.items[i]; + if (id < 0) { + struct crush_bucket *c = map->buckets[-1-id]; + crush_reweight_bucket(map, c); + + if (crush_addition_is_unsafe(sum, c->weight)) + return -ERANGE; + + sum += c->weight; + n++; + } else { + leaves++; + } + } + + if (n > leaves) + bucket->item_weight = sum / n; // more bucket children than leaves, average! + bucket->h.weight = bucket->item_weight * bucket->h.size; + + return 0; +} + +static int crush_reweight_list_bucket(struct crush_map *map, struct crush_bucket_list *bucket) +{ + unsigned i; + + bucket->h.weight = 0; + for (i = 0; i < bucket->h.size; i++) { + int id = bucket->h.items[i]; + if (id < 0) { + struct crush_bucket *c = map->buckets[-1-id]; + crush_reweight_bucket(map, c); + bucket->item_weights[i] = c->weight; + } + + if (crush_addition_is_unsafe(bucket->h.weight, bucket->item_weights[i])) + return -ERANGE; + + bucket->h.weight += bucket->item_weights[i]; + } + + return 0; +} + +static int crush_reweight_tree_bucket(struct crush_map *map, struct crush_bucket_tree *bucket) +{ + unsigned i; + + bucket->h.weight = 0; + for (i = 0; i < bucket->h.size; i++) { + int node = crush_calc_tree_node(i); + int id = bucket->h.items[i]; + if (id < 0) { + struct crush_bucket *c = map->buckets[-1-id]; + crush_reweight_bucket(map, c); + bucket->node_weights[node] = c->weight; + } + + if (crush_addition_is_unsafe(bucket->h.weight, bucket->node_weights[node])) + return -ERANGE; + + bucket->h.weight += bucket->node_weights[node]; + + + } + + return 0; +} + +static int crush_reweight_straw_bucket(struct crush_map *map, struct crush_bucket_straw *bucket) +{ + unsigned i; + + bucket->h.weight = 0; + for (i = 0; i < bucket->h.size; i++) { + int id = bucket->h.items[i]; + if (id < 0) { + struct crush_bucket *c = map->buckets[-1-id]; + crush_reweight_bucket(map, c); + bucket->item_weights[i] = c->weight; + } + + if (crush_addition_is_unsafe(bucket->h.weight, bucket->item_weights[i])) + return -ERANGE; + + bucket->h.weight += bucket->item_weights[i]; + } + crush_calc_straw(map, bucket); + + return 0; +} + +static int crush_reweight_straw2_bucket(struct crush_map *map, struct crush_bucket_straw2 *bucket) +{ + unsigned i; + + bucket->h.weight = 0; + for (i = 0; i < bucket->h.size; i++) { + int id = bucket->h.items[i]; + if (id < 0) { + struct crush_bucket *c = map->buckets[-1-id]; + crush_reweight_bucket(map, c); + bucket->item_weights[i] = c->weight; + } + + if (crush_addition_is_unsafe(bucket->h.weight, bucket->item_weights[i])) + return -ERANGE; + + bucket->h.weight += bucket->item_weights[i]; + } + + return 0; +} + +int crush_reweight_bucket(struct crush_map *map, struct crush_bucket *b) +{ + switch (b->alg) { + case CRUSH_BUCKET_UNIFORM: + return crush_reweight_uniform_bucket(map, (struct crush_bucket_uniform *)b); + case CRUSH_BUCKET_LIST: + return crush_reweight_list_bucket(map, (struct crush_bucket_list *)b); + case CRUSH_BUCKET_TREE: + return crush_reweight_tree_bucket(map, (struct crush_bucket_tree *)b); + case CRUSH_BUCKET_STRAW: + return crush_reweight_straw_bucket(map, (struct crush_bucket_straw *)b); + case CRUSH_BUCKET_STRAW2: + return crush_reweight_straw2_bucket(map, (struct crush_bucket_straw2 *)b); + default: + return -1; + } +} + +struct crush_choose_arg *crush_make_choose_args(struct crush_map *map, int num_positions) +{ + int b; + int sum_bucket_size = 0; + int bucket_count = 0; + for (b = 0; b < map->max_buckets; b++) { + if (map->buckets[b] == 0) + continue; + sum_bucket_size += map->buckets[b]->size; + bucket_count++; + } + dprintk("sum_bucket_size %d max_buckets %d bucket_count %d\n", + sum_bucket_size, map->max_buckets, bucket_count); + int size = (sizeof(struct crush_choose_arg) * map->max_buckets + + sizeof(struct crush_weight_set) * bucket_count * num_positions + + sizeof(__u32) * sum_bucket_size * num_positions + // weights + sizeof(__s32) * sum_bucket_size); // ids + char *space = malloc(size); + struct crush_choose_arg *arg = (struct crush_choose_arg *)space; + struct crush_weight_set *weight_set = (struct crush_weight_set *)(arg + map->max_buckets); + __u32 *weights = (__u32 *)(weight_set + bucket_count * num_positions); + char *weight_set_ends __attribute__((unused)) = (char*)weights; + __s32 *ids = (__s32 *)(weights + sum_bucket_size * num_positions); + char *weights_end __attribute__((unused)) = (char *)ids; + char *ids_end __attribute__((unused)) = (char *)(ids + sum_bucket_size); + BUG_ON(space + size != ids_end); + for (b = 0; b < map->max_buckets; b++) { + if (map->buckets[b] == 0) { + memset(&arg[b], '\0', sizeof(struct crush_choose_arg)); + continue; + } + struct crush_bucket_straw2 *bucket = (struct crush_bucket_straw2 *)map->buckets[b]; + + int position; + for (position = 0; position < num_positions; position++) { + memcpy(weights, bucket->item_weights, sizeof(__u32) * bucket->h.size); + weight_set[position].weights = weights; + weight_set[position].size = bucket->h.size; + dprintk("moving weight %d bytes forward\n", (int)((weights + bucket->h.size) - weights)); + weights += bucket->h.size; + } + arg[b].weight_set = weight_set; + arg[b].weight_set_positions = num_positions; + weight_set += position; + + memcpy(ids, bucket->h.items, sizeof(__s32) * bucket->h.size); + arg[b].ids = ids; + arg[b].ids_size = bucket->h.size; + ids += bucket->h.size; + } + BUG_ON((char*)weight_set_ends != (char*)weight_set); + BUG_ON((char*)weights_end != (char*)weights); + BUG_ON((char*)ids != (char*)ids_end); + return arg; +} + +void crush_destroy_choose_args(struct crush_choose_arg *args) +{ + free(args); +} + +/***************************/ + +/* methods to check for safe arithmetic operations */ + +int crush_addition_is_unsafe(__u32 a, __u32 b) +{ + if ((((__u32)(-1)) - b) < a) + return 1; + else + return 0; +} + +int crush_multiplication_is_unsafe(__u32 a, __u32 b) +{ + /* prevent division by zero */ + if (!a) + return 0; + if (!b) + return 1; + if ((((__u32)(-1)) / b) < a) + return 1; + else + return 0; +} + +/***************************/ + +/* methods to configure crush_map */ + +void set_legacy_crush_map(struct crush_map *map) { + /* initialize legacy tunable values */ + map->choose_local_tries = 2; + map->choose_local_fallback_tries = 5; + map->choose_total_tries = 19; + map->chooseleaf_descend_once = 0; + map->chooseleaf_vary_r = 0; + map->chooseleaf_stable = 0; + map->straw_calc_version = 0; + + // by default, use legacy types, and also exclude tree, + // since it was buggy. + map->allowed_bucket_algs = CRUSH_LEGACY_ALLOWED_BUCKET_ALGS; +} + +void set_optimal_crush_map(struct crush_map *map) { + map->choose_local_tries = 0; + map->choose_local_fallback_tries = 0; + map->choose_total_tries = 50; + map->chooseleaf_descend_once = 1; + map->chooseleaf_vary_r = 1; + map->chooseleaf_stable = 1; + map->allowed_bucket_algs = ( + (1 << CRUSH_BUCKET_UNIFORM) | + (1 << CRUSH_BUCKET_LIST) | + (1 << CRUSH_BUCKET_STRAW) | + (1 << CRUSH_BUCKET_STRAW2)); +} |